Notes for Meteorology 356

November 29, 2004

 

Indira Tutuko

Junko Kato

 

Assignments

Reading: Complete

 

Housekeeping

-Returned Midterm 2 (Average 149/200)

-Reviewed the grade Distribution Chart for Midterm 2

-Final Exam is 15 December 1045-115 PM

We started the class of by returning the second midterm. Midterm Key posted at beginning of class hour. We will discuss systematic problems that appeared in the class for only problematic questions. Professor Monteverdi will take questions about individual grading at the end of class Friday 3 December.

First we started looking at the surface weather map and the plot of 500mb chart for December 15, 1998 to discuss Diablo Winds.  The surface weather map is similar to what we experienced at 3 AM on Saturday, November 27, 2004. During the weekend, we experienced the Diablo wind pattern in winter season. There is also a foot of snow at Tahoe Basin and Mammoth Lake area because of this winter pattern. Over northern California, we observed that there were three isobars during the weekend.

Summer Thunderstorm Pattern

We looked at a surface map and 500 mb weather map on the reader that shows a typical summer pattern of pacific high, north American thermal low, and Bermuda high. This typical summer pattern shows: the jet stream does not locate near us, this pattern produces fog, we have thermal low at the ground, and cumulonimbus clouds move toward us from the southwest. The air from southeast and higher dew temperature usually cause thunderstorm.

Once every 6 years, we experience an episode of thunderstorm. This episode of thunderstorm occurs because:

v    Pacific high moved to the west and weaker than normal. The ocean in eastern pacific is warmer than normal year.

v    Thermal low is located on the edge of the Pacific Ocean. Thermal low should not be on cold water so this means that ocean temperature on Pacific Ocean coast is warmer than normal year.

We also talked about El Ni–o that is usually occurs around Christmas time. El Ni–o happens because the ocean temperature experiences a sudden warming in Eastern Tropical Pacific. In a typical El Ni–o year, there are more intense hurricanes in Eastern Tropical Pacific and we experience lesser fog.